In Daves case the way in which the roaster works is the problem. It is designed so that the beer or whatever liquid you are using to keep the bird moist is outside of the cavity.

I think you're misunderstanding here, Rich. The Weber unit has a cup for the liquid that goes inside the bird as with any of these devices. The big pan is only designed to catch the juices and prevent them from running into your grill. Drilling holes would prevent the runoff from collecting in the pan, but I don't think it's necessary.

That may be, but if you go to the link Dave provided and red the description by Weber I think you will find why I say he is having this problem. Weber's description reads to fill the tray with beer or cider or your favorite liquid. It does not specifically state to fill the cup. Maybe the instructions that come with it read differently, but if you were to follow the directions as I understood them from the web site you would in essence be steaming the outside.

Some gas grills come with infared rotisserrie burners that are level with the food being cooked. I've heard these help with crisping the skins. Infared heat is more directional and radiant which heats up objects directly and not so much the air in between.
Flames on the other hand, heat up the air.
This may make a difference?